Given that Estonia’s coast is [less than a hundred km away from Finland](https://earth.app.goo.gl/?apn=com.google.earth&isi=293622097&ius=googleearth&link=https%3a%2f%2fearth.google.com%2fweb%2f%4060.102175,24.51673043,122.21560592a,697322.55080022d,35y,-10.11456988h,0.13712582t,0r #googleearth), it must be relatively easy for those living there to get across to Finland if they wanted to escape the USSR regime, especially if they lived along the coast.
Did people escape or attempt an escape into Finland, similar to how East Germans escaped into West Berlin?
Similarly did people from Poland or Latvia tried escaping to Sweden via sea? Gotland is very close to the westernmost coast of Latvia, and certain islands of Denmark and southern Sweden are close to Northwestern coast of Poland. Even major cities like Copenhagen and Malmo are close to the northern coast of East Germany. Crossing 50-150km in a small fishing boat doesn’t sound impossible.
How common was it to escape to Finland or Sweden from the Baltic regions and Poland compared to those who went to West Berlin?
EDIT: were there also others fleeing Nazi Germany during world war 2 that used similar routes to get into Sweden or Finland?
There were attempts, but Finnish government was pressured by Moscow to hand over defectors and in practice did so regularly. A 2005 archival survey by Juha Pohjonen discovered that while there was no official agreement to that effect, 75 % of a total of 153 defectors reaching Finnish soil between 1945 and 1981 were returned to the Soviet Union. 36 got either residence permits or asylum in Finland, or were permitted to travel west. The policy had been more lenient until late 1950s, when newly elected president Urho Kekkonen advocated for a stricter line. Kekkonen personally believed that all defectors had to be returned, even if the Finnish intelligence services opposed, and in the 1960s every defector was returned. In the 1970s, only two were granted asylum. Those with Finnish roots or of Finnic ethnicity (like Estonians) were treated slightly more leniently than others.
A good example of the pressure inherent in the situation was the 1977 hijacking of an Aeroflot passenger jet to Helsinki. Two petty criminals had hijacked the plane after its take-off from Petroskoi airport and demanded its pilot to fly to Stockholm. Citing fuel shortage, the captain landed in Helsinki instead. Finnish military was alerted and initially ringed the aircraft with anti-aircraft weapons to prevent Soviet air or airborne attacks, which were perceived to be possible. The hijackers were offered a small plane that they could fly to Stockholm, but they refused the offer. President Kekkonen had ordered that the hijackers must not under any circumstances receive an asylum in Finland; nevertheless, the Soviet ambassador to Finland demanded Finnish police or military to attack the plane, and offered a Soviet special forces group to "assist" the operation - a gross violation of the official neutrality and sovereignity of Finland. These demands were nevertheless rebuffed, and after the last hostages had managed to escape, the hijackers surrendered.
Immediately after the war, Finland had also "repatriated" over 100 000 persons, mostly prisoners of war, volunteers from Estonia who had fought in the Finnish Army (and didn't flee to Sweden in time), but also hundreds of civilians.
If I recall correctly, this was known in Estonia in particular, and was one factor in dampening the enthusiasm for crossing the Gulf of Finland. Another reason was that access to boats, and even to the coast, was soon controlled by Soviet authorities, since many Estonian and other refugees indeed took the sea route to Finland or Sweden until coastal surveillance was tightened. It should also be remembered that the Baltic coast was extensively monitored by Soviet military not just because of defectors, but because it was part of Soviet Union's defensive perimeter.